1. Field of the Invention
The present invention relates to a neck rod member for stringed instruments, particularly for bass guitars. The rod member includes two oblong rod portions which extend parallel to each other and are arranged one above the other. At one end of the rod member, the rod portions are fixedly connected to each other. At the other free ends of the rod portions, a threaded adjustment means is provided for shortening the effective length of one of the rod portions relative to the effective length of the other of the rod portions, so that the rod member is subjected to a corresponding bending force.
2. Description of the Related Art
A neck rod member of the above-described type is known from U.S. Pat. No. 4,852,449. The threaded adjustment means of this known neck rod member makes it possible to curve the rod member into an arc from its neutral position in which the rod member is straight. Consequently, the neck of the instrument in which the neck rod member is mounted also assumes this arc shape. Accordingly, depending on the existing conditions and requirements, the neck of the instrument can be pulled to assume the shape of an arc, wherein the convex side of the arc faces the strings resting on the finger-board of the neck. The above-described bracing action counteracts the relatively strong tension exerted on the neck of the instrument by the strings. Without this bracing action, the danger exists that the tension of the strings will bend or even break the neck of the instrument.
However, in some stringed instruments, particularly in special types of bass guitars, it may be required, for example, due to the grain of the wood of the neck or for other reasons, that the neck rod member should exert a force on the neck of the instrument which is directed in the same direction as the tension force of the strings. In contrast to the convex arc described above, the neck rod member of U.S. Pat. No. 4,852,449 makes it possible to bend the neck rod member mounted in the neck of the instrument into an arc whose concave side faces the finger-board or the strings of the instrument. In other words, it is possible to use the neck rod member for both types of use, wherein the advantages of loosely inserting the rod member into the blind-end hole of the instrument neck and the loose removal therefrom are maintained.
The operation of the neck rod member according to U.S. Pat. No. 4,852,449 is satisfactory. However, the arrangement of the threaded adjustment means, including two different threaded engagements and corresponding adjusting nuts, is quite complicated.